This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Na,K ATPase is an integral membrane protein that regulates the exchange of Na and K in cells. We use the GUV system made of diferent lipids mixtures, including the so called raft-like mixtures to study the distribution of the labeled enzyme in diferent macrodomains. We used two-photon microscopy and Laurdan GP measurements for this characterization.